stolostron
diff --git a/‎go.mod
+12-11 b/‎go.mod
+12-11
diff --git a/‎go.sum
+109-33 b/‎go.sum
+109-33
diff --git a/‎pkg/receive/handler.go
+20-12 b/‎pkg/receive/handler.go
+20-12
diff --git a/‎pkg/receive/handler_test.go
+113-3 b/‎pkg/receive/handler_test.go
+113-3
diff --git a/‎pkg/receive/hashring.go
+6-21 b/‎pkg/receive/hashring.go
+6-21
diff --git a/‎pkg/receive/hashring_test.go
-23 b/‎pkg/receive/hashring_test.go
-23
@@ -1,7 +1,7 @@
 module github.com/thanos-io/thanos
 
 require (
-	cloud.google.com/go v0.74.0
+	cloud.google.com/go v0.79.0
 	cloud.google.com/go/storage v1.10.0
 	github.com/Azure/azure-pipeline-go v0.2.2
 	github.com/Azure/azure-storage-blob-go v0.8.0
@@ -10,6 +10,7 @@ require (
 	github.com/aliyun/aliyun-oss-go-sdk v2.0.4+incompatible
 	github.com/bradfitz/gomemcache v0.0.0-20190913173617-a41fca850d0b
 	github.com/cespare/xxhash v1.1.0
+	github.com/cespare/xxhash/v2 v2.1.1
 	github.com/chromedp/cdproto v0.0.0-20200424080200-0de008e41fa0
 	github.com/chromedp/chromedp v0.5.3
 	github.com/cortexproject/cortex v1.7.1-0.20210224085859-66d6fb5b0d42
@@ -32,7 +33,7 @@ require (
 	github.com/leanovate/gopter v0.2.4
 	github.com/lightstep/lightstep-tracer-go v0.18.1
 	github.com/lovoo/gcloud-opentracing v0.3.0
-	github.com/miekg/dns v1.1.38
+	github.com/miekg/dns v1.1.41
 	github.com/minio/minio-go/v7 v7.0.10
 	github.com/mozillazg/go-cos v0.13.0
 	github.com/mwitkow/go-conntrack v0.0.0-20190716064945-2f068394615f
@@ -47,8 +48,8 @@ require (
 	github.com/prometheus/alertmanager v0.21.1-0.20201106142418-c39b78780054
 	github.com/prometheus/client_golang v1.9.0
 	github.com/prometheus/client_model v0.2.0
-	github.com/prometheus/common v0.15.0
-	github.com/prometheus/prometheus v1.8.2-0.20210215121130-6f488061dfb4
+	github.com/prometheus/common v0.20.0
+	github.com/prometheus/prometheus v1.8.2-0.20210413124018-62afcabd01ea
 	github.com/uber/jaeger-client-go v2.25.0+incompatible
 	github.com/uber/jaeger-lib v2.4.0+incompatible
 	github.com/weaveworks/common v0.0.0-20210112142934-23c8d7fa6120
@@ -57,13 +58,13 @@ require (
 	go.uber.org/atomic v1.7.0
 	go.uber.org/automaxprocs v1.2.0
 	go.uber.org/goleak v1.1.10
-	golang.org/x/crypto v0.0.0-20201208171446-5f87f3452ae9
-	golang.org/x/oauth2 v0.0.0-20210210192628-66670185b0cd
-	golang.org/x/sync v0.0.0-20201207232520-09787c993a3a
+	golang.org/x/crypto v0.0.0-20210220033148-5ea612d1eb83
+	golang.org/x/oauth2 v0.0.0-20210323180902-22b0adad7558
+	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c
 	golang.org/x/text v0.3.5
-	google.golang.org/api v0.39.0
-	google.golang.org/genproto v0.0.0-20201214200347-8c77b98c765d
-	google.golang.org/grpc v1.34.0
+	google.golang.org/api v0.42.0
+	google.golang.org/genproto v0.0.0-20210312152112-fc591d9ea70f
+	google.golang.org/grpc v1.36.0
 	gopkg.in/alecthomas/kingpin.v2 v2.2.6
 	gopkg.in/fsnotify.v1 v1.4.7
 	gopkg.in/yaml.v2 v2.4.0
@@ -80,7 +81,7 @@ replace (
 	// TODO: Remove this: https://github.com/thanos-io/thanos/issues/3967.
 	github.com/minio/minio-go/v7 => github.com/bwplotka/minio-go/v7 v7.0.11-0.20210324165441-f9927e5255a6
 	// Make sure Prometheus version is pinned as Prometheus semver does not include Go APIs.
-	github.com/prometheus/prometheus => github.com/prometheus/prometheus v1.8.2-0.20210215121130-6f488061dfb4
+	github.com/prometheus/prometheus => github.com/prometheus/prometheus v1.8.2-0.20210413124018-62afcabd01ea
 	github.com/sercand/kuberesolver => github.com/sercand/kuberesolver v2.4.0+incompatible
 	google.golang.org/grpc => google.golang.org/grpc v1.29.1
 
 
@@ -4,10 +4,11 @@
 package receive
 
 import (
+	"bytes"
 	"context"
 	"crypto/tls"
 	"fmt"
-	"io/ioutil"
+	"io"
 	stdlog "log"
 	"net"
 	"net/http"
@@ -262,7 +263,7 @@ func (h *Handler) handleRequest(ctx context.Context, rep uint64, tenant string,
 		replicated: rep != 0,
 	}
 
-	// on-the-wire format is 1-indexed and in-code is 0-indexed so we decrement the value if it was already replicated.
+	// On the wire, format is 1-indexed and in-code is 0-indexed so we decrement the value if it was already replicated.
 	if r.replicated {
 		r.n--
 	}
@@ -277,17 +278,24 @@ func (h *Handler) receiveHTTP(w http.ResponseWriter, r *http.Request) {
 	span, ctx := tracing.StartSpan(r.Context(), "receive_http")
 	defer span.Finish()
 
-	// TODO(bwplotka): Optimize readAll https://github.com/thanos-io/thanos/pull/3334/files.
-	compressed, err := ioutil.ReadAll(r.Body)
+	// ioutil.ReadAll dynamically adjust the byte slice for read data, starting from 512B.
+	// Since this is receive hot path, grow upfront saving allocations and CPU time.
+	compressed := bytes.Buffer{}
+	if r.ContentLength >= 0 {
+		compressed.Grow(int(r.ContentLength))
+	} else {
+		compressed.Grow(512)
+	}
+	_, err := io.Copy(&compressed, r.Body)
 	if err != nil {
-		http.Error(w, err.Error(), http.StatusInternalServerError)
+		http.Error(w, errors.Wrap(err, "read compressed request body").Error(), http.StatusInternalServerError)
 		return
 	}
 
-	reqBuf, err := snappy.Decode(nil, compressed)
+	reqBuf, err := snappy.Decode(nil, compressed.Bytes())
 	if err != nil {
 		level.Error(h.logger).Log("msg", "snappy decode error", "err", err)
-		http.Error(w, err.Error(), http.StatusBadRequest)
+		http.Error(w, errors.Wrap(err, "snappy decode error").Error(), http.StatusBadRequest)
 		return
 	}
 
@@ -410,9 +418,9 @@ func (h *Handler) fanoutForward(pctx context.Context, tenant string, replicas ma
 		}
 	}()
 
-	logger := log.With(h.logger, "tenant", tenant)
+	logTags := []interface{}{"tenant", tenant}
 	if id, ok := middleware.RequestIDFromContext(pctx); ok {
-		logger = log.With(logger, "request-id", id)
+		logTags = append(logTags, "request-id", id)
 	}
 
 	ec := make(chan error)
@@ -462,7 +470,7 @@ func (h *Handler) fanoutForward(pctx context.Context, tenant string, replicas ma
 				if err != nil {
 					// When a MultiError is added to another MultiError, the error slices are concatenated, not nested.
 					// To avoid breaking the counting logic, we need to flatten the error.
-					level.Debug(h.logger).Log("msg", "local tsdb write failed", "err", err.Error())
+					level.Debug(h.logger).Log(append(logTags, "msg", "local tsdb write failed", "err", err.Error()))
 					ec <- errors.Wrapf(determineWriteErrorCause(err, 1), "store locally for endpoint %v", endpoint)
 					return
 				}
@@ -525,7 +533,7 @@ func (h *Handler) fanoutForward(pctx context.Context, tenant string, replicas ma
 							b.attempt++
 							dur := h.expBackoff.ForAttempt(b.attempt)
 							b.nextAllowed = time.Now().Add(dur)
-							level.Debug(h.logger).Log("msg", "target unavailable backing off", "for", dur)
+							level.Debug(h.logger).Log(append(logTags, "msg", "target unavailable backing off", "for", dur))
 						} else {
 							h.peerStates[endpoint] = &retryState{nextAllowed: time.Now().Add(h.expBackoff.ForAttempt(0))}
 						}
@@ -554,7 +562,7 @@ func (h *Handler) fanoutForward(pctx context.Context, tenant string, replicas ma
 		go func() {
 			for err := range ec {
 				if err != nil {
-					level.Debug(logger).Log("msg", "request failed, but not needed to achieve quorum", "err", err)
+					level.Debug(h.logger).Log(append(logTags, "msg", "request failed, but not needed to achieve quorum", "err", err))
 				}
 			}
 		}()
 
@@ -26,6 +26,7 @@ import (
 	"github.com/golang/snappy"
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/prometheus/pkg/exemplar"
 	"github.com/prometheus/prometheus/pkg/labels"
 	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/tsdb"
@@ -185,6 +186,108 @@ func TestDetermineWriteErrorCause(t *testing.T) {
 	}
 }
 
+type fakeTenantAppendable struct {
+	f *fakeAppendable
+}
+
+func newFakeTenantAppendable(f *fakeAppendable) *fakeTenantAppendable {
+	return &fakeTenantAppendable{f: f}
+}
+
+func (t *fakeTenantAppendable) TenantAppendable(_ string) (Appendable, error) {
+	return t.f, nil
+}
+
+type fakeAppendable struct {
+	appender    storage.Appender
+	appenderErr func() error
+}
+
+var _ Appendable = &fakeAppendable{}
+
+func nilErrFn() error {
+	return nil
+}
+
+func (f *fakeAppendable) Appender(_ context.Context) (storage.Appender, error) {
+	errf := f.appenderErr
+	if errf == nil {
+		errf = nilErrFn
+	}
+	return f.appender, errf()
+}
+
+type fakeAppender struct {
+	sync.Mutex
+	samples     map[uint64][]prompb.Sample
+	exemplars   map[uint64][]exemplar.Exemplar
+	appendErr   func() error
+	commitErr   func() error
+	rollbackErr func() error
+}
+
+var _ storage.Appender = &fakeAppender{}
+var _ storage.GetRef = &fakeAppender{}
+
+func newFakeAppender(appendErr, commitErr, rollbackErr func() error) *fakeAppender { //nolint:unparam
+	if appendErr == nil {
+		appendErr = nilErrFn
+	}
+	if commitErr == nil {
+		commitErr = nilErrFn
+	}
+	if rollbackErr == nil {
+		rollbackErr = nilErrFn
+	}
+	return &fakeAppender{
+		samples:     make(map[uint64][]prompb.Sample),
+		appendErr:   appendErr,
+		commitErr:   commitErr,
+		rollbackErr: rollbackErr,
+	}
+}
+
+func (f *fakeAppender) Get(l labels.Labels) []prompb.Sample {
+	f.Lock()
+	defer f.Unlock()
+	s := f.samples[l.Hash()]
+	res := make([]prompb.Sample, len(s))
+	copy(res, s)
+	return res
+}
+
+func (f *fakeAppender) Append(ref uint64, l labels.Labels, t int64, v float64) (uint64, error) {
+	f.Lock()
+	defer f.Unlock()
+	if ref == 0 {
+		ref = l.Hash()
+	}
+	f.samples[ref] = append(f.samples[ref], prompb.Sample{Timestamp: t, Value: v})
+	return ref, f.appendErr()
+}
+
+func (f *fakeAppender) AppendExemplar(ref uint64, l labels.Labels, e exemplar.Exemplar) (uint64, error) {
+	f.Lock()
+	defer f.Unlock()
+	if ref == 0 {
+		ref = l.Hash()
+	}
+	f.exemplars[ref] = append(f.exemplars[ref], e)
+	return ref, f.appendErr()
+}
+
+func (f *fakeAppender) GetRef(l labels.Labels) (uint64, labels.Labels) {
+	return l.Hash(), l
+}
+
+func (f *fakeAppender) Commit() error {
+	return f.commitErr()
+}
+
+func (f *fakeAppender) Rollback() error {
+	return f.rollbackErr()
+}
+
 func newTestHandlerHashring(appendables []*fakeAppendable, replicationFactor uint64) ([]*Handler, Hashring) {
 	var (
 		cfg      = []HashringConfig{{Hashring: "test"}}
@@ -1015,6 +1118,10 @@ func (a *tsOverrideAppender) AddFast(ref uint64, _ int64, v float64) error {
 	return a.Appender.AddFast(ref, cnt, v)
 }
 
+func (a *tsOverrideAppender) GetRef(lset labels.Labels) (uint64, labels.Labels) {
+	return a.Appender.(storage.GetRef).GetRef(lset)
+}
+
 // serializeSeriesWithOneSample returns marshaled and compressed remote write requests like it would
 // be send to Thanos receive.
 // It has one sample and allow passing multiple series, in same manner as typical Prometheus would batch it.
@@ -1171,15 +1278,18 @@ func benchmarkHandlerMultiTSDBReceiveRemoteWrite(b testutil.TB) {
 				for i := 0; i < n; i++ {
 					r := httptest.NewRecorder()
 					handler.receiveHTTP(r, &http.Request{ContentLength: int64(len(tcase.writeRequest)), Body: ioutil.NopCloser(bytes.NewReader(tcase.writeRequest))})
-					testutil.Equals(b, http.StatusConflict, r.Code, "%v", i)
+					testutil.Equals(b, http.StatusConflict, r.Code, "%v-%s", i, func() string {
+						b, _ := ioutil.ReadAll(r.Body)
+						return string(b)
+					}())
 				}
 			})
 		})
 	}
 
 	runtime.GC()
 	// Take snapshot at the end to reveal how much memory we keep in TSDB.
-	testutil.Ok(b, Heap("../../"))
+	testutil.Ok(b, Heap("../../../_dev/thanos/2021/receive2"))
 
 }
 
@@ -1188,7 +1298,7 @@ func Heap(dir string) (err error) {
 		return err
 	}
 
-	f, err := os.Create(filepath.Join(dir, "mem.pprof"))
+	f, err := os.Create(filepath.Join(dir, "impr5-go1.16.3.pprof"))
 	if err != nil {
 		return err
 	}
 
@@ -9,14 +9,12 @@ import (
 	"sort"
 	"sync"
 
-	"github.com/cespare/xxhash"
 	"github.com/pkg/errors"
+	"github.com/thanos-io/thanos/pkg/store/labelpb"
 
 	"github.com/thanos-io/thanos/pkg/store/storepb/prompb"
 )
 
-const sep = '\xff'
-
 // insufficientNodesError is returned when a hashring does not
 // have enough nodes to satisfy a request for a node.
 type insufficientNodesError struct {
@@ -39,23 +37,6 @@ type Hashring interface {
 	GetN(tenant string, timeSeries *prompb.TimeSeries, n uint64) (string, error)
 }
 
-// hash returns a hash for the given tenant and time series.
-func hash(tenant string, ts *prompb.TimeSeries) uint64 {
-	// Sort labelset to ensure a stable hash.
-	sort.Slice(ts.Labels, func(i, j int) bool { return ts.Labels[i].Name < ts.Labels[j].Name })
-
-	b := make([]byte, 0, 1024)
-	b = append(b, []byte(tenant)...)
-	b = append(b, sep)
-	for _, v := range ts.Labels {
-		b = append(b, v.Name...)
-		b = append(b, sep)
-		b = append(b, v.Value...)
-		b = append(b, sep)
-	}
-	return xxhash.Sum64(b)
-}
-
 // SingleNodeHashring always returns the same node.
 type SingleNodeHashring string
 
@@ -85,7 +66,11 @@ func (s simpleHashring) GetN(tenant string, ts *prompb.TimeSeries, n uint64) (st
 	if n >= uint64(len(s)) {
 		return "", &insufficientNodesError{have: uint64(len(s)), want: n + 1}
 	}
-	return s[(hash(tenant, ts)+n)%uint64(len(s))], nil
+
+	// TODO(bwplotka): This might be not needed, double check.
+	sort.Slice(ts.Labels, func(i, j int) bool { return ts.Labels[i].Name < ts.Labels[j].Name })
+
+	return s[(labelpb.HashWithPrefix(tenant, ts.Labels)+n)%uint64(len(s))], nil
 }
 
 // multiHashring represents a set of hashrings.
 
@@ -10,29 +10,6 @@ import (
 	"github.com/thanos-io/thanos/pkg/store/storepb/prompb"
 )
 
-func TestHash(t *testing.T) {
-	ts := &prompb.TimeSeries{
-		Labels: []labelpb.ZLabel{
-			{
-				Name:  "foo",
-				Value: "bar",
-			},
-			{
-				Name:  "baz",
-				Value: "qux",
-			},
-		},
-	}
-
-	ts2 := &prompb.TimeSeries{
-		Labels: []labelpb.ZLabel{ts.Labels[1], ts.Labels[0]},
-	}
-
-	if hash("", ts) != hash("", ts2) {
-		t.Errorf("expected hashes to be independent of label order")
-	}
-}
-
 func TestHashringGet(t *testing.T) {
 	ts := &prompb.TimeSeries{
 		Labels: []labelpb.ZLabel{